Process of refining oils and the like by steam treatment



Patented May 14, 1935 UNITED smrss PRocEs's' F REFINING oiLs AND THELIKE BY STEAM TREATMENT Georg Zotos, Gharlottenburg, Germany ApplicationJuly 2, 1931,, Serial No. 548,427

In Germany March 3 1930 V 3 Claims.

In carrying out the process, steam is gener-v ated at a pressure ofabout 200 atmospheres and superheated to a temperature of about 500 C.This steam is employed, for instance for the cracking of heavy oils, theheat being transferred to the latter. Owing to the high pressure, thetransference of heat can be effected up to the saturation temperature,in this case about 364 C. At this comparatively high temperature it ispossible to utilize most if not all of the heat of vaporization in theprocess itself so as to convert the steam into hot condensate which caneasily be withdrawn from the apparatus. The hot water under pressure canbe employed in a heat exchanger for preheating the fresh water used forthe steam generation, the entire heat being thereby recovered.Alternately the condensate can be returned to the steam generator forrenewed conversion into steam.

The condensation of the steam during the process can be effected invarious manners, for instance by the preheating of materials with thesteam or by dephlegmation, cooling or the like according to the resultaimed at.

The invention is illustrated in the accompanying drawing whichrepresents a diagrammatic view of an apparatus whereby the process canbe carried out.

The device comprises a reaction chamber I wherein the materials, forinstance heavy oils, are treated by direct heat interchange with steamproduced in a generator 2 at a pressure of about 200 atmospheres andsuperheated to about 500 C. This steam, after having transferred itsexcess heat to the materials, is led into a second, upright pressurevessel 3 wherein oil is treated by the steam before it is fed into thechamber I. By the further transfer of heat in the vessel 3, the steam iscondensed, and the condensate, still under pressure, is collected at thebottom 4 of the vessel. The oil is mostly incapable of mixing with thewater and forms, on the surface of the latter, a layer 5 whence it canbe fed into the chamber I. The hot condensate under pressure is fed intoan intermediary collector 6 whence it can be returnedjby means of a pumpH into the generator 2 for renewed conversicninto'ste'am; Alternately;the highly heated water can be passed through a heat exchanger vessel 7for preheating fresh water fed by means of a pump 8 from a tank 9 intothe steam generator'2.

Under the influence of the condensing steam, the oil in the dephlegmatoracquires a temperature which renders its decomposition in the reactionchamber by the superheated steam ex- 10 tremely'" easy. This favourabletemperature is obtained owing to the high pressure of the steam. Thepressure may be lowered somewhat, andthe oil may be retained for alonger period in the dephlegmator than in the reaction chamber if aparticularly refined product is. aimed at. For rapid cracking, however,the oil is retained for a longer period in the reaction chamber. Forhydrating purposes, the pressure must be as high as possible, the Workbeing carried on with an excess of steam as compared with the oil.

The water soluble substances contained in the materials and carried awaywith the condensate, are removed from the latter before itsre-introduction into the steam generator 2. This can be eifected in avessel l4 in known manner, for instance by lixiviation with suitableknown reagents capable of dissolving the phenols and oxides or by afractional cooling in which the oil is automatically disengaged. Thistreatment of the Favourable combinations of reaction chamber I bythrottling the steam at I2, in which case a pump 13 must be used forfeeding the oil from the vessel 3 into the chamber l, or part of thecold water under pressure may, for condensing the steam in the vessel 3,be

passed through the latter at Hi. It is not necessaryto carry out theprocess in two vessels in succession, since the heat interchange andcondensation of the steam under pressure can be effected in a singlevessel.

The above described process can be employed in all cases when thematerials are to be subjected to high pressure and to temperaturesbetween 250 C. and 600 C. Coal paste may be treated together withhydrogen containing materials for liquefaction, and hydrocarbons and taroils may be refined in this manner. Various hydration processes can becarried out in this manner, in which case the steamis used not only as aheating medium butalso as a reagent in known manner.

The employment of the highly superheated steam according to the presentinvention, does not exclude thesimultaneous use of difi'erent,chemically acting gases and vapours such as air, oxygen, hydrogen,carbon oxide, ammonia, sulphur dioxide and the like which may beintroduced together with the steam through a pipe I 5.

The time of reaction is determined, as is usual in the art, by thenature of the raw material under treatment.

The process according to the invention has many technical advantages. Bythe employment of superheated steam a large yield of heat can beobtained from camparatively small apparatus, and the saving of heat bycarrying out the process according to the present invention isconsiderable.

I claim:

1. A process of cracking mineral tar oils and similar substances,comprising feeding the initial substance through a dephlegmating zoneinto a reaction zone, generating steam at a pressure of about 200atmospheres, feeding said steam at such pressure and at a temperature ofabout 500 C. through the reaction zone into the dephlegmating zone,condensing the major portion of the steam in .the dephlegmating zoneinto water under pressure, and utilizing said water under pressure inthe steam generation.

2. The process claimed in claim 1 including the step of feedingchemically reacting gases together with thesteam into the reaction zone.

3. The process claimed in claim 1 including thestep of separating fromthe condensate substances dissolved in the latter during the crackingprocess. v

GEORG ZOTOS.

